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<p class="heading">Assembler Directives - MEMORY<hr noshade></p>
<p></p>
<p><b>MEMORY</b> - Defines the access level for a range of memory. Four access 
types are supported. They are:</p>
<p><b>&nbsp;&nbsp;&nbsp; ROM<br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </b>Memory 
may be read or written but the writes have no effect.<br>
<b>&nbsp;&nbsp;&nbsp; Read<br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </b>Memory 
may be read from but not written to. Any attempt to write to the memory results 
in a bus error exception.<br>
<b>&nbsp;&nbsp;&nbsp; Protected<br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </b>Memory 
may only be accessed when the Supervisor flag is set in the Status Register. 
Accessing the<br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; memory when 
the Supervisor flag is not set results in a bus error exception.<br>
<b>&nbsp;&nbsp;&nbsp; Invalid<br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </b>Any 
memory access results in a bus error exception.</p>
<p>Memory not specified in a specific range is assumed to be RAM. RAM may be 
read or written. </p>

<p class="sourcecode">Usage:<br>
[label]&nbsp;MEMORY <i>type startAddress,endAddress</i></p>

<blockquote>

<p>Where <i>type</i> is ROM, Read, Protected or Invalid. startAddress and 
endAddress must evaluate to a valid 24 bit address. <br>
&nbsp;</p>
</blockquote>
<p class="sourcecode">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; MEMORY&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
ROM&nbsp; $001000,$002000<br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; MEMORY Protected&nbsp; 
$00F000,$00FFFF</p>

<p>The memory map information is saved in the .S68 (<a href="../SRecordDescription.htm">S-Record</a>) file generated by 
the assembler in the form of S0 records. The EASy68K simulator uses the 
information from the S0 records to set the memory map on the
<a href="../SIMHELP/Hardware.htm">hardware form</a>.</p>
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